A report into last June's flooding shows most mud tanks in South Dunedin weren't properly maintained.

The Dunedin City Council report highlights serious inadequacies within the organisation and its maintenance contractor Fulton Hogan.

It also states heavy rainfall on the 3rd of June last year was the highest in a 24-hour period in almost a century.

It's believed that even if all mud tanks were up to standard, flooding would still have damaged the city.

But the council's planning to improve its maintenance and management of infrastructure.

It's also set on engaging further with the community about associated issues.